A 13-day old baby presented to her local hospital with respiratory distress and a history of poor feeding for a few days. The baby had no history of maternal risk factors for infection and had normal antenatal scans. At the time of referral, she was self- ventilating in air with sternal and subcostal recession. She had a 2/6 systolic murmur and a firm liver, enlarged to her umbilicus. Pre- and post-ductal saturations were 92% on admission with upper limb/ lower limb blood pressure as shown in Table 52.1. CXR identified cardiomegaly and opacification of the right lung fields. Her abdomen was distended but soft. She had microscopic blood present on urine bedside testing. She was sleepy but responsive with a flat fontanelle. The referring hospital had sent relevant blood tests as noted in Table 52.2 and commenced IV cefotaxime.